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A200977
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Smallest number expressible in the form a^2 + 2b^2, with positive integers a and b, in exactly n ways.
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0
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3, 27, 99, 297, 891, 1683, 8019, 5049, 18513, 15147, 649539, 31977, 314721, 136323, 166617, 95931, 10673289, 351747, 64304361, 287793, 1499553, 8450649, 127680201, 863379, 20160657, 99379467, 5979699, 5180274, 1235641473, 3165723, 50984802, 3933171
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OFFSET
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1,1
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COMMENTS
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Incidentally all terms are multiples of 3.
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LINKS
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EXAMPLE
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3 = 1+2*1^2.
27 = 3+2*3^2 = 5^2+2*1^2.
99 = 1+2*7^2 = 7^2+2*5^2 = 9^2+2*3^2.
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CROSSREFS
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Cf. A154777 (numbers of the form a^2 + 2b^2 with positive integers a, b).
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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